Process of producing paraffinic oils



April 1944- A. M. McAFEl-i ETAL ,3

PROCESS OF PRODUCING PARAFFINIQOILS 1 Filed April 25. 1941 content.

Patented Apr. 25, 1944 UNITED STATES PATENT OFFICE 2,347,274 PROCESS PRODUCING PARAFFINIC OILS Almer M. McAfee and Edward E. Dunlay,, Port Arthur, Tex., assignors to Gulf Oil Corporation, Pittsburgh, Pa., a corporation of Pennsylvania Application April 25, 1941, Serial No. 390,376

14 Claims.

further comprises subjecting relatively high boiling fractions of the oils thereby produced to catalytic cracking in the presence of aluminum chloride catalysts, which may be catalyst sludge recovered from the initial reaction.

In U. S. Patent No. 1,608,328 to McAfee there is described a process of synthesizing oil in which residual oils, such as asphaltic reducing crudes and other residual oils having relatively high carbonzhydrogen ratios are subjected to contact with gases rich in hydrogen in the presence of alu minum chloride and at high temperatures, that is to say at 500 F. or higher, thereby effecting a condensation of the gases and the oils to form oils of averaged composition with lower asphaltic a number of ways and particularly in that production of gasoline, if any, was an incidental feature rather than the principal object of the process. In cracking processes, however, gasoline production was the principal object.

oils employed are non-residual and non-asphal tic oils intermediate in boiling range between gasoline and lubricating oil fractions; they are distillates or distillate fractions as distinguished from residual oils or reduced crudes.

The present invention. unlike the process of Patent No. 1,608,328, is not concerned with the carbonzhydrogen ratios of the reacting gases and bon:hydrogen ratio, are employed. In many cases, the carbonzhydrogen ratio of the olefinic gases will be higher than the carbonzhydrogen ratio of the oil treated.

Referring to the oil used as one of the starting materials, we prefer to employ oils of the character generally known as solar oils, particularly those produced from coastal crudes and containing large or even predominating amounts of naphthenic. and aromatic constituents. Corresponding distillates from highly paraflinic crudes, such as Pennsylvania crudes, are less suitable. As aforesaid, suitable oils are those intermediate the boiling point range of gasoline on the one 15 hand and light lubricating oil fractions on the That process was distinguished from prior aluminum chloride cracking processes mar;

other hand. Straight run distillates may be employed but the invention is not so limited and we have in fact applied our invention successfully to sulfur dioxide extracts of kerosenes from California and other highly asphaltic crudes. The boiling point range of the starting material will run from about 400 to 700 F.

The gases employed in accordance with our invention are olefin-containing gases such as refinery gases and particularly gases produced in cracking petroleum oils, as well as individual actions thereof. We have found that such gases should contain at least about 30 per cent :f unsaturated constituents, and preferably 50 per cent or more of unsaturates. Our invention, in one advantageous aspect, contemplates the reaction of propylene or gases r ch in propylene with oils of the character indicated above for the production of valuable oils, especially Diesel oils. This particular embodiment of the invention is' especially useful and advantageous in view of the fact that large quantities of propylene are usually available in refineries having little value as such and are difllcult to convert into able fuels for Diesel engines having high cetane oils; the gases may be higher or lower in carbonzhydrogen ratio than the oil. As a matter of fact, our process is especially advantageous where highly unsaturated gases, of relatively high carnumbers, as well as superior. charging stocks for catalytic cracking operations.

In practicing our invention, oiefinic gases are contacted with non-residual oils of the character 'is desired to. do so. recovered in the aforesaid distillation may, as

aforesaid in the presence of anhydrous aluminum chloride or other aluminum halide catalyst at temperatures not higher than about 250 I, but preferably above about 100 F. and under low or atmospheric pressure, usually not ex- I ceeding 100 pounds per square inch. The process' is advantageously conductedby leading a stream of the gases into and through, a'body. of

the oil, containing aluminum chloride, in a suitable reaction vessel, and withdrawing from the vessel the gases not consumed in the reaction "together with any volatile products producedduring reaction which may readily be removed from eflluent gases by absorption or condensaltion. Under ordinary conditions the boiling range of the products will run from approximately 100? F. to about 709? F. Those products which are notremoved filth the eflluent gases remain in the reaction vessel and may be withdrawn continuously orintermittentlyas desired.

When the reaction is once started it proceeds indefinitely so long as the supply of gases and oil is maintained, and-with suitable replenishment of the catalyst. Ordinarily the amount of catalyst maintained in the catalyst zone will run from .5 to 25 per cent by weight, based on the amount of oil charged to the reaction zone;

However, the actual consumption of catalyst in the process is far lower. It is ordinarily necessary only to supply suflicient catalyst to replace that necessarily withdrawn-from the reaction vessel in suspension in the heavy products.

45 A. P I. gravity. In a particularly advantageous, continuous embodiment of our process.

we start with refinery gases anda solar oil or the like having an- A. P. I. gravity of about to and proportion the relative feeds of gas and oil and the withdrawal ofreaction products in such manner as to maintain in and withdraw from the reaction zone a 40 A. P. I. 011.

'A further way of stating our preferred procedure for continuous operation is that we prefer to use higher gas-oil feed ratios with more highly aromatic or naphthenic oil charges and with less highly olefinic gases. On the other hand we prefer to use lower gas-oil feed ratios with less highly aromatic 'or naphthenic oil charges and with more highly olefinic gases. Between the two extremes of, on the one hand, very highly aromatic or naphthenic oils plus low olefin-content gases'and, on the otherhand, relatively low aromatic or naphthenic oils plus high olefincontent gases, the ratio of gas feed to oil feed will vary over a considerable range.

An important object ofour invention is to react refinery gases with aromatic or naphthenic oil distillates or the like to producemore highly paraflln'ic oils especially those containing large amounts or even predominating amounts of isoparafiins. The above-stated preferred conditions ofcontinuous operation have been found by us tgjbetmost conducive to the attainment of this 0 cc y In order that our invention may be clearly set forth and understood we now describe, with reference to the drawing accompanying and forminga Part of this specification, a specific manner'and embodiment in which our invention may be practiced and embodied. In this drawing,

voline fraction and a higher boiling fraction, but

intermediate cuts may be taken oi! whenever it The high boiling fraction jected to catalytic cracking, especially in the presence of aluminum chloride. While fresh anhydrous aluminum chloride maybe used in this subsequent cracking operation, .we have found that the catalyst sludge separated from the products leaving the initial reaction 'zone may be advantageously used'in the subsequent cracking operation.

This cracking operation is ordinarily conducted by simply distilling-the high boiling 011 in the' presence of, the; catalyst and removing and condensing the vaporized products leaving the still.

The distillation is ordinarily carried to a point where the residue remaining in the still is dry.

'One of the advantages achieved by means of our process is the fact that the gasoline produced in the subsequent cracking operationrepresents a fully saturated high octane number product containing large quantities of isoparamnicconthe singleflgure is a more or less diagrammatic elevational view of apparatus suitable for carrying out the process of our invention. v

Referring to the drawing, a slurry of aluminum' chloride in solar oil or the like is introduced from a suitable source (not shown) through a line I into a high speed contactor 2, which maybe q pped With any suitable means (not shown) for recirculation and for maintaining the con tents at a suitable temperature, advantageously stituents and-may be used alone or blended with other fuelsas, for example, the gasoline distillate produced in the initial reaction.

In a typical continuous embodiment of our process where high boiling oil, fresh :catalyst and refinery gases are continuously supplied to products so as to maintain in and withdraw from the reaction zone an oil having about a 3 3. to

to 250 F. Refinery gases from a source not shown are introduced through a line 3 into contactor 2 and therein intimately contacted with the above-mentioned slurry. A mixture of slurry, reaction products and unreacted gases-is withdrawn througha line 4 and introduced into a separator j provided with a cone-shaped bottom 6, a weir land a sight-device 8. Vapors and gases from the slurry rise through the fractionatmg column 9 and unreacted gases leave the system through the line 40. Liqueflable hydrocarbons are condensed in column 9 and refluxed to separator To assist in separating the unreacted gases from the condensable products, and also to supplymake-up oil, solar oil or, other naphthenic or aromatic high boiling oil is introduced into the top or column 9 through the line ride slun'y settles into the bottom cone section 6 and the reaction products overflow weir I and are drawn off through the line I2 by means of the pump l3. Control of the oil level is bad by sight device 8. The aluminum chloride slurry of the slurry and oil is recirculated by the pmnp lsthrough the-line iii to line (and thus back to In theseparator 5 the heavier aluminum chlocontactor 2. Another part is completely removed from the system through the line IT. This latter portion may then be used as a catalyst for cracking the high boiling portion of the reaction products as subsequently described.

The greater part of the reaction products, free from aluminum chloride, is introduced through line I! by pump I3 into the fractionating column where the products are separated into a distillate of aviation gasoline, which is withdrawn through the line 2 I, and a higher boiling portion, which is withdrawn through the line 22. Part of this higher boiling portion of the reaction products is pumped by the pump 23 through the line 24 to line l6 and thus through line I back to contactor 2. Another part is removed from the system through the line 25 and may be further fractionated to produce heavier oil fractions than .aviation gasoline for use as high cetane Diesel fuel or superior charging stock for cracking, or

drocarbons predominate, and high boiling oils in which naphthenic hydrocarbons predominate. The refinery gases used in this example analyzed as follows:

' Per cent by volume Air 1.1 Hz, CH4 L Nil CrH4, CzHs Nil Cal-Is, CzHa 3.4 C4Ha, C4H1o 95.3 Acid gas Nil Unsaturation 74.0

The high boiling oil used in this example was a solar oil distillate from Gulf coastal crude in I which naphthenic hydrocarbons predominate.

There are some aromatic hydrocarbons also present in this type of oil. The solar oil distillate had the following inspection:

2500 parts by volume of the solar oil (amounting to approximately 2225 parts by weight) were charged to a reaction vessel equipped with a stirrer. parts 'by weight of anlwdrous aluminum chloride were added to the oil. The temperature of the contents of the flask was brought to 180 F., with vigorous stirring. At this time, aluminum chloride had formed a slurry with a portion of the oil and was suspended throughout the body of the oil. The refinery gases, analyzing as above, were slowly and continuously added to the vessel. The temperature was held in the range of 180 F. to 200 F. at atmospheric pressure. From time to time, fresh aluminum chloride, as such, or as a slurry, was added in small increments sufficient to maintain the desired rate of reaction. At the end of 76 hours. the reparts by volume of low boiling. liquid hydrocarbons were recovered by condensation from the exit gases. These low boiling hydrocarbons had the following inspection:

Gravity A. P. I 56.9

The oily reaction product remaining in the reaction vessel amounted to 11,400 parts by volume, and had the following inspection:

Gravity A. P. I 39.4 Distillation, .A. S. T. M.:

Over point F 156 End point F 705 10% at F 358 50% 560 680 Recovery Per cent 93 Example 2.--2500 parts by volume of the 39.4 A. P. I. oily reaction product obtained in Example 1 were charged to the same apparatus of Example l. The same quantity of aluminum chloride as in Example 1 was added and the contents of the reaction vessel were brought'to 180 F., with vigorous stirring. Refinery gases as used in Example 1 were slowly and continuously led into the vessel while holding the temperature at 180 F. to 200 F. at atmospheric pressure. At the end of '72 hours, the reaction was stopped. During this time, a total of parts by weight of aluminum chloride were added. 1740 parts by volume of low boiling, liquid hydrocarbons were recovered from the exit gases during this '72 hour reactionperiod. These low boiling hydrocarbons had the following inspectionz' Gravity A. P. I 55.3 Distillation, A. S. T; M.:

Over point -F 118 End point F- 295 10% at ..F 158 50% 195 90% 250 Octane No., C. F. R.-A. S. T. M Above 90 Gum and corrosion:

Mg./ 100 cc 7 The oily reaction product remaining in the vessel amounted to 10,800 parts by volume, with the following inspection:

Gravity A P. I 42.0 Distillation, A. S. T. M.:

Over point F End point F 700 10% at F 390 50% '594 90% 690 Recovery 1 94 Example 3.--2500 parts by volume of the 42.0 A. P. I. oily reaction product obtained in Example 2 were charged to the same apparatus of Example 1 along with the same quantity of aluminum chloride as employed in the previous example. Refinery gases as used in Examples 1 and 2 were led into thev reaction vessel and the contents were 6'75 75 held at a temperature of 180 F. to 200 F. for a.

period ores hours. Approximately 90' parts by weight of aluminum chloride were added at. intervals. During thecourse oi. the. reaction, 1170 parts by volume of low boiling, high octane number liquid hydrocarbons were obtained from the oil were drawn-from the flask. This oil, which A portion of this oil was charged to a stirring still and distilled in the presence of 5 per cent by weight of aluminum'chloride. ;The overhead distillate amounted to per cent of the oil charged and had the following inspection:

This distillate was'then fractionated to give a.

36 per centyield of gasoline having the following inspection:

Gravity 'A. P. I 69.5 Distillation, A. S. T. M.: f

' Over point F 126 End point F 312 10% at 159 50% 201 256 Recovery Per. cent 98 Octane No., C. F. R..-A. S. T; M 80.5 Gum and corrosion: 1

Man/100 cc 2 Example 4.--This example is illustrative of th reaction between refinery gases in which C; hydrocarbons predominate, and high boiling naphthenic type oils. The refinery gases used in this exampleanalyzed as followsi Percent by volume 'Air, hydrogen, methane Nil Ethane, ethylene i. 10.9 Propane, propylene 60.7 iButane, butyle 28.3 n-Butane- Nil Acid gas 0.1 'Unsaturates 43.4

The high boiling oil used was a solar oil similar to that in Example 1.

2,500 part by-volume of the solar oil were charged to a reaction vessel equipped with. a

stirrer. A weight of anhydrous aluminum chloride same as before was added to the oil in the reaction vessel. The temperature or the contents of the iggction vessel was then brought to approximately reaction vessel while the contents were held within the temperature range of F. to F. From time to time, fresh aluminum chloride, as such, or as a slurry in solar oil, was added in small increments sufiicient to maintain the de- F., with vigorous stirring. The' Ca refinery gases were slowly and continuously added to the Gravity -A. P- I.

Distillation, A. S. T. M.:

Over point F 78 End .pnin F 610 1 a F '132" 50% 295 .Recovery Per cent-.. 96

Gravity fA. P. I 24.8

Distillation, A. S. T. M.: I

Over point.- -1 F 360 Endpoint ..F 545 10% at"--. F 385 50% i 437 90% 492 i to maintain the ,desired rate of condensation.

the reaction was stopped. At that time a total of 370 parts by weight of aluminum chloridehad been added. No low boiling liquid hydrocarbons were recovered from the exit gases during the run. 10,000 parts by volume of highly parafiinic was a high octane number Diesel fuel t p of product, had the following inspection:

Gravity"; A. P. I 38.6 Distillation, A. S. T. M.:

- Over point- F 246 End point F 688 10% at F., 439

Thus it will be observed that by reacting refinery gases in which Ca hydrocarbons predominate with a highly naphthenic'solar oil, a large yield of excellent Diesel fuel oil can be advantageously made.

Example 5.This example is illustrative of the reaction between refinery gases and high boiling oils in which aromatic hydrocarbons largely =predominaten The high boiling oil used in thi example was'that portion of kerosene-soluble in liquid sulfur dioxide. As is well knowrnliquid sulfur dioxideextracts the aromatic hydrocarbons.

The particular aromatic oilused in this example had the following test:

' The refinery gases used in this example were the same as used in Example 4. 2500 parts by volume or the aromatic oil were'charged to a reaction vessel equipped with a stirrer. Again- 50 parts by weight of anhydrous aluminum chloride were added to the oil in the reaction vessel. The temperature was then brought to approximately 140 F., with, vigorous. stirring. The refinery gases were slowly and continuously added to the vessel while the contents were held within the tempera-v ture range of 135 F. to F. From time to time fresh aluminum'chloride, as such, or as a slurry, was added in small increments sufiicient At the end of 96 hours, the reaction was stopped.

At that time a total of 200 parts by weight of aluminum chloride had been added. No low boiling liquid hydrocarbons were recovered from the exit gases during the run. 11,000 parts by volume ofhighly parafiinic oil were drawn from the reaction vessel. This 011 had the following inspection:

Gravity; A. P. I 37.1 Distillation, A. S. T. M.: Over point F .155

End Point, F 700 10% at F 430 50% 606 90% 700 action, aromatic hydrocarbons are converted into sired rate of reaction. At the'end of 120 hours, 75

The high A. P. I. gravity of the reaction product indicates a high content of paraflinic hydrocarbons. Thus it will be observed that by this reparaifinic hydrocarbons.

While we have described our invention with particular regard to certain specific embodiments and examples, our invention is not limited to such range, to contact with each other in the presence of an aluminum halide catalyst, at a temperature not higher than about 250 F.

2. The process of producing highly parafllnic synthetic oils, which comprises continuously passing a stream of olefin-containing gases through a body of non-residual hydrocarbon oil, high in non-parafiinic and non-asphaltic constituents and substantially free from hydrocarbons boiling within the gasoline boiling point range, in a reaction zone maintained at a temperature of not more than about 250 F., in the presence 01' an aluminum chloride catalyst, supplying additional oil and catalyst to the reaction zone, and removing efliuent gases and liquid reaction products from the reaction zone as formed.

3. The process of claim 1, wherein the oil consists substantially entirely of constituents boiling between 400 and 700 F.

' 4. The process of claim 1 wherein the oil is a solar oil distillate recovered from a naphthe'nic crude oil.

5. The process of claim 1 wherein the oil is an S: extract of kerosene distillate from a naphthenic crude oil.

6. The process of claim 1 wherein the gases contain at least 30 percent by volume of unsaturated hydrocarbons.

7. The process 01' claim 1 wherein the gases predominate in propylene.

8. A continuous process for producing parafllnic oils including substantial amounts of iso-paratfinic hydrocarbons boiling in the gasoline boiling point range from refinery gases and oils which are non-paraflinic in character, which comprises reacting a refinery gas containing not less than about 30 per cent by volume of olefins with a non-residual, non-asphaltic hydrocarbon oil of non-paramnic character having an A. P. I. gravity not greater than about 30 and largely free from hydrocarbons boiling in the gasoline. boiling point. range in the presence of aluminum chloride, maintaining a reaction temperature between about 100" and 250 F., continuously supplying sald gas and said oil to the reaction mixture and replenishing the aluminum chloride, continuously removingfrom the reaction mixture unreacted gases, used aluminum chloride, a gasoline .fraction of substantially parafllnic character having a high octane number and congasoline fraction which is largely paraflinic in character and has an A. P. I. gravity between about 35 and 45.

9. The process of claim 8 wherein said nonasphaltic hydrocarbon oil or non-paraflinic character is a solar oil distillate recovered 'from a naphthenic crude oil. I

10. The process of claim 8 wherein said refinery gas contains propylene as the predominant olefin.

11. The process of claim 8 wherein at least a portion of said oil traction of 35 to 45 A. P. I. gravity is distilled in the presence of aluminum chloride and a fraction is separated from the distillate consisting of gasoline boiling point range parailin hydrocarbons.

12. A process of producing high octane number gasoline which comprises contacting refinery gases containing substantial amounts of olefins with a non-residual, non-asphaltic hydrocarbon oil of non-paraflinic character, substantially free from gasoline boiling point range hydrocarbons, in the presence of aluminum chloride at temperatures not above about 250 F., thereby forming a reaction product which is lighter and more parafllnic than the initial oil, and at least partly converting the aluminum chloride into a sludge, separating unreacted gases and a substantially saturated, paramnic high octane number gasoline fraction from said reaction product, and distilling at least a portion of the remainder of said reaction product in the presence of said aluminum chloride sludge, thereby producing a further quantity of saturated, high octane number paraflinic gasoline.

13..A process o! producing high cetane number Diesel fuel from refinery gases and hydrocarbon oils of relatively poor motor tuel value, which comprises contacting refinery gases containing substantial quantities 01' olefins with a non-residual, non-asphaltic hydrocarbon oil of non-parafllnic character in the presence of aluminum chloride at temperatures not greater than about 250 11., thereby producing a lighter oil of essentially paraflinic character, separating unreacted gases, gasoline and aluminum chloride from said oil, and i'ractionating the remaining oil to produce a parafiinic out of high cetane number and of boiling point and volatility range suitable for AIMER. MIMCAFEE. EDWARD E. DUNLAY. 

